Abstract
Bing-Neel syndrome (BNS) is a rare complication of Waldenström macroglobulinemia, characterized by lymphoplasmacytic lymphoma infiltration of the CNS. We present a pathologically confirmed case of BNS in a patient who was initially misdiagnosed with COVID-19 pneumonia and critical illness polyneuropathy. This case underscores the diagnostic challenges associated with BNS and highlights the importance of early recognition.